• Bufospirostenin A (1), an unusual steroid

• It is used as anti cancer agent and possess cardioactive effect

• Structurally, it contains ü Unusual [5-7-6-5-5-6] ring systemü First spirostanol found in animalsü 11 Sterocenters: 10 contiguous, 2 quaternary, 1

spiroketalü No total synthesis reported

Lakshmi RLiu Research Group

Total synthesis presentation12/09/2020 1

Asymmetric Total Synthesis of Bufospirostenin AM.-J. Cheng, L.-P. Zhong, C.-C. Gu, X.-J. Zhu, B. Chen, J.-S. Liu, L. Wang,* W.-C. Ye,* and C.-C. Li*

Cheng et al., J. Am. Chem. Soc. 2020, 142, 12602

Bufospirostenin A (1)

Retrosynthetic analysis of Bufospirostenin A (1)

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